Bacterial vaginosis (BV) is the most common vaginitis and results from increased infection of non-single pathogenic bacteria (bad bacteria) that prefers basic environment due to elevated vaginal pH and is usually accompanied by a reduction of the normal Lactobacillus flora (probiotic) in the vagina. The common pathogens include Gardnerella, Escherichia coli, Candida albicans, Candida tropicalis, Streptovecido vaginalis, Prevotella and Proteus (Mastromarino P. et al., New microbiologica, 2013, 36, 229-238).
The infected women have the symptoms such as vaginal itching, vaginal odor, and abnotinal discharge. At present, two methods are available for diagnosis of BV: (1) Amsel criteria, identification of three out of the four following clinical symptoms will give a confirmed diagnosis: watery, gray, and white vaginal discharge attached to the vaginal wall; the vaginal pH is greater than 4.5; Whiff test: the discharge has a foul ammonia smell (foul-smelling fishy odor) in the presence of 10% KOH; the smear specimen shows a large number of bacteria adsorbed in the vaginal epithelial cells under the microscope and the cells are granular or clue cells with dotted appearance; (2) according to the Nugent score, a Gram stain scoring system for vaginal swab, a Nugent score ≥7 or 4-7 along with the presence of clue cells in the specimens will give a confirmed diagnosis of BV.
About the treatment for BV, the most common treatment is oral or topical administration of antibiotics, such as Metronidazole; however, use of antibiotics not only kills the pathogens of BV, but also leads to the death of the normal flora in the vagina. In addition, the growth of probiotic bacteria in the body is usually slower than pathogens and therefore medication usually will result in decreased immunity of patients which consequently changes the vaginal bacterial patterns in the patients and leads to repeated infections or even interferes with the treatment by generating drug-resistant pathogens. Moreover, there is also a potential risk of side effects of drugs. Despite the treatment of Metronidazole has significant clinical efficacy, there is still a relapse rate as high as 50% and the inevitable drawbacks of the antibiotics, and these are difficult problems that need to be addressed. Hence, searching for alternative drugs or treatments that have no side effects, higher efficacy and reduced recurrence is the major topic in the recent studies associated with BV (Hongying T. et al., Archives of Gynecology and Obstetrics, 2017, 295, 1331-1339).
In terms of indicators of treatments for BV, the aforementioned pathogens, changes of probiotics, and the inflammation, are associated with activation of the immune response and therefore the expression of the molecules relating to immune regulation is also a basis for reference, among which IL-10 and IL-12 are the immunoregulators that are produced in large amount upon invasion of pathogens and these two will co-express to promote immune defense and regulate immunologic homeostasis in a host (Ma X. et al., F1000 Research, 2015, 4 (F1000 Faculty Rev), 4, 1465). In addition to IL-10 and IL-12, Dmitry V. et al. also described the roles of IL-1β and IL-6 in bacterial infections in 1996 and these two are cytokines that promote inflammation. IL-1β promotes phagocytosis of bacteria by the immune cells in a host and IL-6 helps clearance of bacteria by neutrophils via a non-phagocytic way and regulates inflammation (Dmitry V. et al., Int. J. of Antimicrobial Agents, 1996, 1, p33-40). After administration of drugs, the reduced expression of IL-6 indicates alleviation of inflammation at the infected site, which means improvement in inflammation. Changes in the expression of the aforementioned cellular immunoregulators can be used as efficacy indicators for treating bacterial infection.
From the recent literatures, oral administration of probiotic (Lactobacillus) helps to restore the balance of normal flora in the vagina of the patients with BV after receiving the treatment of antibiotics. In the study published by Jean et al. in 2015, a new-generation drug for treating BV was proposed, Tinidazole, which can be used alone or in combination with Lactobacillus reuteri RC-14 and Lactobacillus rhamnosus GR-1 in patients, the probiotic bacterial flora of Lactobacillus iners and Lactobacillus crispatus in the vagina of patients showed a significant increase by detection of 16sRNA, a combination of antibiotics and probiotics is helpful for restoration of the floral patterns in the patient's vagina and prevention of the risk of recurrence (Jean M. et al., Microbial Ecology in Health & Disease, 2015; 14; 26: 27799). Likewise, in 2015, Piotr B. et al. indicated that the combination of antibiotics Metronidazole with prOVag® containing 3 probiotic strains (including Lactobacillus gasseri 57C, Lactobacillus fermentum 57A, and Lactobacillus plantarum 57B) can effectively extend the relapse time, reduce the vaginal pH and increase the number of Lactobacillus in the vagina of the patients with BV after receiving routine treatment of antibiotics.
Based on the aforementioned studies, the combined use of probiotics and antibiotics helps to prevent recurrence but the administration of antibiotics may still have problems, such as side effects, drug resistance, and high relapse rate. Therefore, some studies also tried to avoid the use of antibiotics and examined whether administration of probiotic composition alone can treat bacterial vaginosis. Related patents are briefly described as follows.
TW 1542353 discloses a food composition and/or pharmaceutical composition for treating vaginitis, comprising at least one Lactobacillus strain which is gastric acid, bile salt and Clotrimazole-resistant and is selected from the strains of Lactobacillus acidophilus F-1 and Lactobacillus rhamnosus CT-53 or the combination thereof, can inhibit expression of tumor necrosis factor-α (TNF-α) and interleukin-10(IL-10) and can further inhibit the symptoms of inflammation of the vaginal mucosa cells and can be orally administered or topically applied to the affected site. Nonetheless, said composition was primarily tested based on the direction of immunoregulation and the strains survived in the gastrointestinal tract were screened by bile salt, acid resistance and antifungal agents. However, the main cause of vaginitis is increased pathogens and reduced probiotic bacteria. The invention simply demonstrates its regulation of immunoregulators and alleviation of symptoms but fails to prove its effect on the flora in the vagina, provides no efficacy evaluation for the affected site in the patients and shows no evidence of reduction of the high relapse rate of vaginitis.
CN 105263504A reveals a bacterial composition for prevention and/or treatment of bacterial vaginosis, vaginitis and Escherichia coli pathogens and/or Gardnerella-associated vaginal infections, said bacterial composition comprising LMGP-21021 (LP01) or LMG P-21020(LP02) and DSM26955 (LF15) or DSM26956 (LF16), said composition can inhibit the growth of Escherichia coil and Gardnerella vaginalis and induce the release of immunoregulators IL-4 and IL-10, said composition was prepared by combination of the bacteria strains and tara gum and was given to patients as vaginal tablets for clinical testing, the aforementioned tara gum plays the role of a physical barrier for pathogenic microorganisms. According to the results, 24 hours and 48 hours after administration of the tablets showed the highest inhibitory activity against Gardnerella vaginalis and was effective in blocking acute infections caused by Gardnerella vaginalis. The Lactobacillus composition of the present invention is combined with tara gum and administered as vaginal tablets. The composition can effectively reduce the Nugent scores of patients in the clinical trial, but the key feature of the present invention is that the tara gum can be applied to the affected site and form a physical barrier against pathogens to prevent acute infection. Therefore, the dosage form must be vaginal tablets or other routes that can be applied to the affected site directly. Because the affected site of the patients with vaginitis is relatively a hidden site, the vaginal tablets are not a convenient and fast route of administration. The affected site is rather fragile and inadvertent use may lead to secondary injury in the patients. Hence, how to treat vaginitis without the restrictions on dosage forms while reducing the recurrence rate is still a problem yet to be solved.
In light of the above, the inventor has successfully developed the composition comprising of the groups selected from Lactobacillus rhamnosus GMNL-680 and Lactobacillus plantarum GMNL-682 for prevention and treatment of bacterial vaginosis and regulation of immunity.